nobosemasita.

The dictionary form is のぼせる.

So the breakdown is:

• のぼせる = dictionary/plain form
• のぼせました = polite past form

This is an ichidan verb (a る-verb), so it changes like this:

• のぼせる → plain non-past
• のぼせます → polite non-past
• のぼせた → plain past
• のぼせました → polite past

ました makes the verb both:

• polite
• past

So のぼせました means that the action or state happened already, and the speaker is saying it politely.

Very roughly:

• のぼせた。 = plain/casual
• のぼせました。 = polite

This is the standard ます-form past tense.

Japanese often leaves out the subject when it is understood from context.

So のぼせました。 could mean:

• I got overheated / lightheaded.
• He got overheated.
• She got overheated.
• They got overheated.

In real conversation, the listener usually already knows who the sentence is about.

If you wanted to make it explicit, you could say:

• 私はのぼせました。 = I got overheated.

But in many situations, that sounds more explicit than necessary.

No. They sound related, but they are different verbs.

• のぼる（登る / 上る） usually means to go up, to climb, to ascend
• のぼせる means to become overheated, to feel faint/lightheaded from heat, or sometimes figuratively to get carried away

So のぼせました does not mean climbed.

That is a very common point of confusion for learners because the sounds are similar.

It usually refers to becoming unwell from heat, especially in situations like:

• staying too long in a hot bath
• being in a sauna
• getting overheated

A common image is:

• お風呂でのぼせました。 = I got overheated / lightheaded in the bath.

Depending on context, it can suggest:

• dizziness
• faintness
• flushed, overheated discomfort

So it is not just hot in a neutral sense. It usually means the heat affected someone physically.

Yes. Besides the physical meaning, it can also be used figuratively.

For example, it can mean someone is:

• carried away
• overexcited
• infatuated
• blinded by enthusiasm or emotion

But if you see のぼせました by itself, many learners will first meet it in the physical heat/lightheaded sense.

So context matters a lot.

Because in Japanese, a complete sentence can consist of just a predicate if the rest is understood.

Here, のぼせました already contains the main idea:

• what happened
• the tense
• the politeness level

Japanese often omits things like:

• the subject
• the location
• the cause

if they are obvious from context.

So even though it is only one word in Japanese, it can still be a full sentence.

It is very often written in hiragana as のぼせる / のぼせました.

There are kanji spellings such as:

• 逆上せる
• sometimes 上せる in certain contexts

But for many learners, and in a lot of everyday writing, hiragana is the most common and safest form to recognize.

So seeing のぼせました in all hiragana is completely normal.

Yes, it can be natural by itself, especially as a short response or explanation.

For example:

• どうしたんですか。
  のぼせました。

This feels like: What happened? — I got overheated.

However, if you want to be clearer, Japanese often adds context:

• お風呂でのぼせました。 = I got overheated in the bath.
• 少しのぼせました。 = I got a little overheated.

So the short version is natural, but context usually tells the listener exactly what is meant.

The casual past form is のぼせた.

Compare:

• のぼせました。 = polite
• のぼせた。 = casual

And the non-past forms are:

• のぼせます。 = polite non-past
• のぼせる。 = casual/dictionary form

So if you are speaking to friends, you might hear のぼせた instead.

Usually it is a past statement, because of ました.

So the most direct reading is:

• got overheated
• became lightheaded

But depending on the situation, English may sometimes phrase the result more naturally as:

• I’m overheated.
• I feel faint from the heat.

That is because Japanese past forms often describe a change that has already happened, while English may focus on the current result.

So grammatically it is past in Japanese, but the most natural English translation can depend on context.